O Ensino de ligações químicas por meio do conceito de energia: uma proposta didática para o ensino médio

This work presents discussions on the teaching of Chemical Bonds in high school and some implications of this approach in learning chemistry by students. In general, understanding how the chemicals combine to form substances and compounds, it is a key point for understanding the properties of substances and their structure. In this sense, the chemical bonds represent an extremely important issue, and their knowledge is essential for a better understanding of the changes occurring in our world. Despite these findings, it is observed that the way in which this concept is discussed in chemistry class has contributed, paradoxically, to the emergence of several alternative designs, making the understanding of the subject by students. It is believed that one of the explanations for these observations is the exclusive use of the "octet rule" as an explanatory model for the Chemical Bonds. The use of such a model over time eventually replace chemical principles that gave rise to it, transforming knowledge into a series of uninteresting rituals and even confusing for students. Based on these findings, it is deemed necessary a reformulation in the way to approach this content in the classroom, taking into account especially the fact that the explanations of the formation of substances should be based on the energy concept, which is fundamental to understanding how atoms combine. Thus, the main question of the survey and described here of the following question: Can the development of an explanatory model for the Chemical Bonds in high school based on the concept of energy and without the need to use the "octet rule"? Based on the concepts and methodologies of modeling activity, we sought the development of a teaching model was made through Teaching Units designed to give subsidies to high school teachers to address the chemical bonds through the concept of energy. Through this work it is intended to make the process of teaching and learning of Chemical Bonds content becomes more meaningful to students, developing models that contribute to the learning of this and hence other basic fundamentals of chemistry.

A influência das questões de gênero nos processos avaliativos escolares

This paper aims to discuss the influences of gender issues in formal and informal evaluation processes in order to identify situations that may lead to exclusion of boys and girls in our schools. Therefore, we rely on the authors as Freitas (2005, 2006, 2011), Sordi (2009), Villas Boas (2006), Fernandes (2006, 2008), (Carvalho (2001.2004, 2011), Blonde (1995, 2003), Scott (1995), Connell (1995), Navy (2009), Dal'igna (2004), among others. These authors help us understand that both gender issues as the evaluation questions in its formal and informal when analyzed, especially in light of school reality, are impregnated with socially constructed conceptions that are reflected in the school. The survey was conducted in two rooms of the 5th year of elementary school, and the genres of research were qualitative and quantitative. In the development of this study, the research followed those steps: School Rules analysis, grade maps, class journals; Mapping of records of the evaluation results of the 1st to 5th year of elementary school; Analysis of official government documents in education; development, implementation and analysis of questionnaires answered by the students and the teachers with issues about gender and evaluation; Mapping of the evaluation results of the students of two classes surveyed during 2012; Observation in the classroom; interview with the teachers of the surveyed groups. During the research we found that gender issues are not dealt with by the school and that this reinforces some exclusion processes that are linked to these questions. Studies also tell us that on the surveyed groups most of the children who have lower evaluative results are boys, which, in the evaluation of teachers, are considered undisciplined. Of the children with poor results, 50% are black. Some of these children who had low evaluative income have not completed the school year in that school. The study also reveals that on the observed groups, generally the girls have better results in formal assessments than boys, which are considered, by the teachers, more undisciplined and difficult to work with. The girls, on the other hand, are considered more docile and attentive than boys. The observations made by teachers concerning the behavior of boys and girls also reflect in the formal evaluative results, therefore the informal assessments, the value judgment of teachers in relation to the behavior of the students influence the results of formal assessments. In this sense, in order to seek ways to try to overcome the exclusion situations experienced in the evaluation process, we believe that the principles of popular education can be configured as an important parameter to begin discussions on gender and evaluation in schools.